Echobradley

Have a bit of a problem with my 98 SLK230. Was running rough and had fuel trim error 0170 and misfire codes. Now will not keep running. Dies in 2 seconds every time. Starts fine and then shuts off. Fuel pressure is 50-60lbs and keeps 60 after it dies so it seems not to be fuel. Cleaned MAF, checked for air leaks, battery disconnected several times to clear codes, even overnight. Plugs are nearly new. No codes showing but dies every time. Cannot keep running by moving accelorator. Checked K40 pcb and resoldered, powered each relay, checked all fuses, seems fine. Looked fine before soldering. Unplugged MAF to see if it will run, still dies. Was able to get it to idle twice very briefly when disconnected air intake tube, but not consistant. Anybody have this problem before or have some thoughts? thanx!

ChromeBenz

It sounds like you may have a key malfunction. try with a spare key and see what happens

Echobradley

The car was stripped of everying not bolted down when I got it. No floormats, air compressor, tools, manuals, etc. Just one key. I was thinking it could be a key/anti-theft issue but it did idle ok for a bit twice with the air intake tube off. Any guess if the anti-theft was activated if it would generate an error code? I have tried starting it likely 30 times in the last week or two working on it.

muskratbenz

Following a tow - I am having the same problem. But because the tow was a result of a broken intake camshaft, which I later replaced, I have been reluctant to blame it all on the key. I did some research on the DAS system though, and from what I could tell the car starts with a mechanical turn, and then the DAS looks for an all okay from the respective modules (ECU/TCU/PSE, etc.). If it does not get an okay for an authorized start, then it cuts the engine by opening the fuel return line, via the k40. Have done a lot of the same things you have - resoldered K40, swapped MAF's, changed plugs, put in another Fuel Pressure Regulator, disconnected various sensors just to see if I could some variation in the response - but it always does the same barely start then die. I am at wits end, still fighting this thing. I have Carsoft 7.4, and a multiplexer, and have done every possible voltage test I could think of - thinking that maybe I screwed up a connector or pinched some wires while putting in the cam, or fouled up a module with all the oil that littered the engine compartment during this. I have no answers for you - but would gladly compare notes. I did manage, during pulling modules and cleaning connectors, to get a nice idle for about five minutes, but upon restart it went back to the same - start, idle for 2 seconds, then sputter and die. Working on it again today, so we will see. PM me with your number and I'll call so we can compare notes. My SLK is also a pre-facelift model ('99).

v-twin

Same problem here with 99 slk230. It cuts out after started for 2 seconds.
Have any of you guys find the problem?

Echobradley

Hi V twin. Mine is nearly done but I have to replace my supercharger as it was leaking oil and kept coating my MAF. I had weeks of problems and hours trying to figure out what was causing my car to shut off after 3 seconds. After checking fuel pressure, vacuum, (checking for leaks) and looking over sensors I could not come up with any specific cause. I replaced the ignition coils (cracked) and plugs but they didn't seem to make much difference. I eventually got it to idle but it was really rough. I replaced the MAF and it ran much better but I ended up taking it to a dealer and they confirmed too much oil leaking from my supercharger (131,000 miles). I had cleaned my MAF a few times and it didn't seemt to help the old one that much. I am not sure why it would not run for a few weeks but it eventually started to idle roughly and then replacing the MAF helped, but did not cure. I wrote to Muskratbenz but have not heard any updates from him lately. He had the same issue and has put in tons of time trying to figure out the problem. I think the computer does a variety of checks when the car first starts and if something is bad, it will shut the car down. Watch fuel pressure closely and check for any fault codes. I have posted a lot more of this problem and specifics on Benzworld.ORG (not com) under the R170 dies after 3 second posting. Hope this helps, sorry, no specific fix for you but will be glad to give any help possible. One place to check is the K40 relay board, it has a history of solder problems that can affect the fuel system.

v-twin

Any updates on this problem? is it the coil ?

Echobradley

Hi Vtwin. I currently have the car apart replacing the supercharger and cleaning all the intake tubes and intercooler of oil contamination. The biggest thing that seemed to get it running again was a new MAF but the oil from the supercharger was coating the MAF and would cause it to run horrible. I purchased a rebuilt s/c and will hopefully have it in this week. Holidays and stuff slowed me down. Any progress on your slk?

v-twin

the car is park 30 something miles away at a warehouse. I haven't had the time to actually go up there to really look at it. I'll after Jan 12 since i'm so busy right now.

Thanks for the update.

v-twin

clean the MAF and it ran again, but it still very rough. i was thinking of purchasing a new MAF... if you bought yours from ebay, it is probably a Chinese counter part product. Buy the sensor insert for 139 and it should run again.

btw, i've done alot of research and found that the oil contamination is not from the SC. it is from the crankcase breather hose. The partial load valve failed. check it out.

Echobradley

Thanks Vtwin! I am just now getting mine going after installing a rebuilt supercharger. I was getting lots of oil coating the MAF and tubes, and it seemed to be oil that was not so dirty. I finally took got it to the dealer and they diagnosed it as the supercharger leaking oil. After assembling and cleaning out the intercooler I have it running but not completed. If for some reason it still gets oil through it I will check that part out. It was SO much oil that it would acting up again after only a day or two after cleaning the MAF. Thanks again for your update ! ! !

muskratbenz

Been busy with a handful of projects, sorry for the delay in posting this.
I did end up buying a new MAF - although I was suspect on this as the actual source of my problem. By itself, this did not resolve my problem, although it did seem to want to run a little longer. I also went ahead and sort of bootleg replaced a lot of my ignition wiring harness. Those wires were ridiculously crisp and brittle, and it's difficult to imagine they didnt have a negative impact on engine startup. I also noticed that two of my plugs were wet and that the four plug o-rings on the valve cover were in crappy shape and could easily let oil through which would short the harness and foul the plug.
End result - car runs better than ever. Wish I could tell you what the exact culprit was. I suspect that the MAF and the crappy ignition wiring combined to create faults that might mimic CAN communication faults. But that's just a theory.